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On the mechanics of functional asymmetry in bipedal walking.

ABSTRACT: This paper uses two symmetrical models, the passive compass-gait biped and a five-link 3-D biped, to computationally investigate the cause and function of gait asymmetry. We show that for a range of slope angles during passive 2-D walking and mass distributions during controlled 3-D walking, these models have asymmetric walking patterns between the left and right legs due to the phenomenon of spontaneous symmetry-breaking. In both cases a stable asymmetric family of gaits emerges from a symmetric family of gaits as the total energy increases (e.g., fast speeds). The ground reaction forces of each leg reflect different roles, roughly corresponding to support, propulsion, and motion control as proposed by the hypothesis of functional asymmetry in able-bodied human walking. These results suggest that body mechanics, independent of neurophysiological mechanisms such as leg dominance, may contribute to able-bodied gait asymmetry.

SUBMITTER: Gregg RD

PROVIDER: S-EPMC4201655 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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On the mechanics of functional asymmetry in bipedal walking.

Gregg Robert D RD Dhaher Yasin Y YY Degani Amir A Lynch Kevin M KM

IEEE transactions on bio-medical engineering 20120207 5

This paper uses two symmetrical models, the passive compass-gait biped and a five-link 3-D biped, to computationally investigate the cause and function of gait asymmetry. We show that for a range of slope angles during passive 2-D walking and mass distributions during controlled 3-D walking, these models have asymmetric walking patterns between the left and right legs due to the phenomenon of spontaneous symmetry-breaking. In both cases a stable asymmetric family of gaits emerges from a symmetri ...[more]

PMID: 22328168

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